BACKGROUND: Elderly patients are currently underrepresented in cancer clinical trials. As a result, new evidence may not be generalizable to the population group that carries the greatest burden of illness. Access to clinical trials also offers patients the opportunity to receive the newest treatments and meticulous clinical care. In order to ensure that the clinical trial system is relevant and accessible to all patients with cancer, it is important to identify specific barriers to the enrollment of elderly cancer patients. SPECIFIC AIMS: 1) To identify demographic and clinical characteristics of elderly cancer patients that are associated with clinical trial participation; 2) To identify institutional and organizational determinants of trial participation for elderly cancer patients; 3) To identify research centers that are particularly successful in enrolling elderly cancer patients into clinical trials, and determine whether the investigators' attitudes and enrollment strategies at these centers are different from those at centers that are less successful at enrolling elderly patients; and 4) To identify attitudes of elderly cancer patients towards participation in clinical trials. RESEARCH PLAN: First, we will perform a population-based analysis of barriers to the participation of elderly cancer patients with breast, prostate, lung, and colon cancer in clinical trials sponsored by the National Cancer Institute. The SEER-Medicare data will be used to estimate characteristics of incident cancer patients in the population. We will analyze the impact of patient and hospital characteristics, and health system factors such as managed care market penetration on the recruitment of elderly patients. Guided by these findings, we will then perform qualitative studies of elderly cancer patients as well as clinical investigators to ascertain their attitudes toward the participation of elderly patients in clinical trials. CAREER DEVELOPMENT PLAN: My career goal is to become an independent investigator, focusing on the quality of care for elderly patient with cancer-specifically on how new cancer therapies for elderly patients are evaluated and disseminated. In order to attain the necessary skills, I will work closely with my mentors on a rigorous program of research and independent study. Additionally, I will receive formal training in the Masters of Public Health program in Health Policy and Administration. SIGNIFICANCE: We hypothesize that patient reluctance, investigator attitudes, and the lack of insurance coverage for direct medical costs are crucial barriers to trial participation for elderly cancer patients. It is our hope that this work will facilitate the development of targeted and novel approaches to overcoming these barriers.